Excavator



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NOV- l2. 1929. J. E. MATTINSCN ET AL 11,735,122 ExcAvAToR Filed May 17. 1926 2 Sheets-Sheet l4 l. ..,.....v., 45.2.1, ,fir QI@ html; m. .Lav ...r .n

, J. E. MATTINSON ET AL Nov. 12, 1929.

EXCAVATOR Filed May 1'7. 1926 2 Sheets-Sheet 2 Patented Nov. 12, 1929 iran stares savana .estaca JESSE E. MATTNSON AND ERNEST J'. MOODY, 015 SAN FRNGSCO, CALIFORNIA n EXCAVATOR Application med May 17, 1926, serial No. 109,471, and in canada May 17, 1926.

Our invention relates to excavators, and more particularly to excavators for use in mining operations. 1

An object of our invention isto provide an 5 excavator that can excavate material and load it into cars without swinging the dipper.

Another object of our invention is to provide an excavator having a dipper from which the dug material dischargesV solely l0 thru the elevation of the dipper.

Another object of the invention is to pro'- vide an excavator in which the dug material discharges from a dipper to a conveyor when the dipper is elevated.

Another object of the invention is to provide an excavatory in which the lifting cables have ample leverage on the dipper in all positions thereof. K

Another object of the inventionis to provide an excavator in which a support isprovidedy for the front end of the conveyor which extends over the rotatable platform.

The invention possesses other advantageous n features, some of which with the foregoing,

description where -we shall outline in -full that form of the kexcavator` Vof our invention which we have selected for illustration in the drawings accompanying and forming part of the present specification.V In said drawings we have shown one form of excavator embodying our invention, but it is tov `be understood that we do notk limit ourselves to. such form since the invention as set forth in the r claims K.may be embodied in a plurality of forms.

ln the drawings:V A v l Fig. l is side elevation of the machine of our invention. j i Fig. 2 is a section on tli line 2 2 of Fig.

l of the machine of our invention, showing particularly the arrangement in plan of the rotatable platform. '1 y Fig. S is a front view of the machine.

Fig. l is aperspective view showing particularly the dipper and purchase arms.V

y Broadly speaking, the excavator of our invention preferably comprises a base provided with a dipper mounted on the base for universal movement and adapted to discharge 5 will be set forth at length in the followingV material collected in the dipper thru the dipper handle onto a conveyor also mounted on the base.

In mining operations, for which work our excavator 1s especially adapted, it is necessary to handlelarge quantities of loosened earth or similar material which has been broken down from the face of the workings. This material must be loaded into cars for removal from the mine, and excavators or shovelingmachines are employed for this purpose. Thefexcavator is preferablyrad- '.Vanced on tracks as the work proceeds and -thesetracks carry the mine cars into which 'he material is loaded by the excavator.

In the operation of such excavators hitherto, the dipperV of the machine was lowered and crowded into the lbank aheadA of it to charge the dipper with material. Then the dipper was full, it was elevated sufficiently to clear the cars and was swung from the front of the shovel approximately thru a semi-circle until it was directly above a car to the rear of the shovel. The bottom of the dipper was then dropped and the excavated material fell into Athe car. The bottom of the dipper was closed and the dipper was again swung thru a semi-circle to its former position in front ofthe shovel. It was next lowered and the cycle of operations was repeated. It is apparent that .a narrow tunnel will preclude the use of an excavatorof this type,.s ince there is not suiiicient room for the dipper to swing from its excavating position to its car loading position.

The excavator of our invention is designed especially for operation in a narrow tunnel. To this end, we provide al machine adapted to be run into the end of a tunnel and which can excavate and load material without swinging the clipper in a semi-circle from the front to the rear of the machine. In our machine, the dipper handle is formed like a chute and the material collected in thev dipper runs by gravity down the dipper handle when the cipper is raised. Fromv the dipper handle, the material is discharged onto al belt conveyor which runs rearwardly of the machine and carries the material from the dipper handle to the car.

The preferred form of our eXcavator, which is illustrated in the drawings, comprises a base or carriage 6 preferably provided with wheels 7 which have the usual flanges 8 for operation on railway tracks 9, and in addition are exceptionally Wide so that the base or carriage may be driven onto the earthwork at the end of the track without the necessity of providing rails. Pivotally mounted upon the carriage is a rotatable platform 11 which is provided with a central journal 12 adapted to turn about a short supporting column 13 resting on the carriage v6. An annular track 14 is laid upon the carriage directly beneath a bull gear wheel 16 affixed to the underside of the rotatable platform 11. A plurality of spaced rollers 17 are interposed between the lower face of the bull gear 16 and the upper side of the track 14 in order to carry some of the weight of the rotatable platform and to permit freerelative rotary movement between the platform and the base 6.

Means are provided for rotating the platform with respect to the carriage. In the preferred embodiment of the machine, the means for rotating the platform is driven by the same motor which provides power for propelling the carriage. An electric motor 18 is mounted at the rear end of the carriage 6 and drives a shaft 19 by means of a silent chain 21. At each end of the shaft 19, dog clutches 22`are provided. A cooperating dog clutch 23 mounted on a squared shaft 24 is adapted to engage the front dog clutch 22 and imparts the rotation of the shaft 19 to the shaft 24. At the front end of the shaft 24 a mitre gear 26 engages a corresponding mitre gear 27 mounted on a shaft 28 which carries vat its upper end a spur pinion 29 engaging the bull gear 16. A second cooperatingl dog clutch 31 is mounted on the front endf' of'a squared sha-ft 32 and is adapted to engage thefrear dog clutch 22 on the shaft 19. The rear end of the shaft 32 carries a bevel gear 33 which meshes with a cooperating bevel gear 34 mountedy on the driving axle 36 of the carriage 6. 1t is deemed eX- pedient to make the plat-form rotating means and the carriage propelling means alternatively operative. The two cooperating dog clutches 23 and 31 which slide on their respective squared shafts, are linked together by means of shifting forks 37 attached to the underside of the carriage and connected by means of a shift-ing rod 38. At each end of the shifting rod 38 a suitable electric solenoid 39is situated and is adapted to pull the rod 38 toward itself. A suitable electrical control 41 is provided for the solenoids whereby they may be energized separately or together. One solenoid may be energized to engage the dog clutches 22 and 31 to the rear of the shaft 19 and cause the electric p motor 18 to propel the carriage 6 in either direction depending upon the direction of rotation of the motor. Alternatively the other solenoid may be energized to cause the front dog clutch 22 to be energized whereby the shaft 24 is rotated and the rotatable platform is turned with respect to the carriage in either direction, depending upon the direction of rotation of the electric motor 18.

The supporting column 13 about which the rotatable platform 11 is journalled rests firmly upon the base 6 at its lower end, and at its upper end supports the front end of the conveyor 42. The conveyor may be of any desired type such as a` belt conveyor or a chain conveyor and while in the present instance it is preferably made of a plurality of interconnected links which present a substantially continuous surface to the material to be handled, it is for convenience referred to as a belt conveyor. Such conveyors are well known and need not be described in detail. The front portion of the conveyor rests on the supporting column 13 which is mounted on the carriage and slopes upwardly to a supporting structure comprising a steel framework 43 resting upon theV rear portion of the carriage. The conveyor is slanted toward the front of the machine in lorder to overlie as closely as possible the rotatable platform. Since the conveyor is supported at its front end on the supporting column 13 and at its rear end on the steel framework 43, it is very rigidly held in place and can withstand comparatively large loads. The sides of the conveyor are enclosed by suitable side pieces 44 preferably made of steel sheets over a skeleton steel framework and aid in maintaining the excavated material upon the conveyor. The front end of the conveyor belt 46 is turned about a pair of sprocket wheels 47 mounted on a shaft 48 journalled in the framework. The shaft is connected by suitable gearing and speed reducing mechanism 49 to an electric drive motor 51 mounted preferably on a bracket 52 formed at one side of the upper end of the supporting column 13. The rear end of the sloping portion of the conveyor gives onto a level ordischarging portion 53 of the conveyor which is mounted on the steel framework 43 and eX- tends over the track 9 above the cars 54. In order to be readily elevated and depressed within fairly wide limits, the level portion 53 is pivoted at its front end on a transverse shaft 56 pivotally supported in' the steel framework 43 so that the entire discharge portion 53 of the conveyor may be suitably 57 are formed which rest upon the upper end of jack screws 58 suitably mounted in brackets 59 secured to an extended portion of the supporting framework. The 'jack screws are engaged by suitably threaded mitre gears 61 which mesh-with Corresponding mitre gears 62 journalled on a transverse shaft. A 1ongitudinal shaft 63 extends from a bevel gear 64 engaging one of the mitre gears 61 to a pointforwardly of the machine and terminates in a hand wheel 66 conveniently located for operation by the operator of the excavator; By suitably turning the ,hand wheel, the discharging or level portion 53 of the conveyor may be raised or lowered a Considerable distance in order to position it Correctly over the cars 54 whichreceive the excavated material. i

At the front end of the rotatable platform 11 means are provided for supporting therexcavatingdipper and dipper handle. In the present instance the support comprises two masts 67 solidly mounted upon the rotatable platform and suitably braced. A short distance above the rotatable platform a transverse Crowder shaft 68 is journalled in suitable blocks 69 supported by the two masts. The Crowder shaft carries at its outer end a gear wheel 71 which is meshed by a pinion 72 mounted on a sub-shaft 73 journalled in one of the masts andL in an auxiliary support 74. The sub-shaft is rotated by a pinion 76 on the driving motor 77 which meshes with a large gear 78 on the sub-shaft. By suitably energizing the electric motor 7 7 the crowder shaft 68 can be rotated in either direction by means of the intermediate mechanism.l

To give the hoisting cables 79 of the dipper a large amount of leverage, purchase arms 81 are pivotally mounted on the Crowder shaft adjacent each mast. Each purchase arm 81 comprises a radial arm having a projecting tongue or key 82 which is adapted to engage in a suitable channel or keyway 83 mounted j at either side of the bottom of the unitary dipper and dipper handle. The unitary dipper handle and dipper 84 are preferably construct-ed of heavy sheets of material bent into the requisite shape and securely riveted together and carry on the bottom a centrally located rack 86 which meshes with a pinion 87 on the Crowder shaft 68. Excavating teeth 88 of tough material are attached preferably to the forward end of the dipper. The dipper handle is a continuation of the dipper and is formed like a Chute or trough. Operation of the Crowder shaft 68 in either direction propels or retracts the unitary vdipper and dipper handle by means of the engagement of the Crowder pinion and the crowder rack. The keys or projections 82 slide in the keyways or guides 83 and at the same time aid in support-ing the unitary dipper and dipper handle 84 although they allow it free movement.

At convenient points on the dipper the two hoisting cables 79 are suitably attached and pass upwardly from the dipper over pulleys 89 mounted at the outer end of the purchase arms 81 and thence proceed upwardly to a pair of pulleys 91 mounted at the upper end of the masts 67 from whence they proceed downwardly to pulleys 92 j ournalled adjacent the bottom of the masts and then extend rearwardly to winding drums 93. The winding drums are usually two in number and are mounted on a common shaft 94 journalled on the rotatable platform 11. A suitable electric motorA 96 is provided for revolving the winding drums in either direction and accomplishes its purpose by ymeans of interposed spur gearing 97. Operation of the hoisting motor 96 will revolve the winding or hoisting drums 93 in the proper direction and will haul in or pay out the hoisting cable 79. The movement of the hoisting cable is transmitted to the dipper 84 andi impels a corresponding motion thereof. c

By providing purchase arms 81 over which the hoisting cable can pass, the hoisting cable can exert considerable leverage on the dipper even though the dipper is in its lowermost retracted position, as shown in the dotted lines in Fig. 1. This is an important advantage inasmuch as the dipper inV this position usually has but little leverage exerted upon it, even though it is in a position in which leverage is most needed. The purchase arms 81 turn inaccordance with the motion of the dipper handle 84, and as they approach a vertical position leave their Contact with the cable passing between the dipper and the pulleys 91 on top of the mast and swing freely for an instant until they engage the Cable passing between the pulleys 91 and the pulleys `92 at the bottom of the mast. When the pulleys 89 on the purchase arms come into Contact with the cables between the pulleys 91 and the pulleys 92, they take up whatever slack there may be in the cables and act as a shock absorber for the dipper.

Suitable controls 98 for the various electric motors are grouped in a convenient location at the forward end of the rotatable platform at which point a seat 99 is provided for the operator of the excavator. A switch box 41 containing switches controlling the various solenoids 39 and for controlling the conveyor motor 51 is mounted within convenient reach of the operator.

In the operation of the machine, by suitable manipulation of the solenoids, dog clutches, and the propelling motor, which is controlled by one of the controllers on the front platform, the carriage or base is driven under its own power to its position of work at the face of the mine working. Suitable operation of the proper solenoid then vdisengages the dog clutch 23 and connects the propelling motor 18 to the gearing 29 for rotating the rotatable platform 11. rIhe conveyor motor 51 is set in operation and the conveyor 46 then operates in a direction to Carry excavated material toward the rear of the machine. The controllers 98 areoperated simultaneously to ipay out the hoisting cable 7 9 and run the orowder mechanism 87 to force the dipper 8l vinto the bank ahead of it and fill it with m..- terial. The crowder motor 77 and the hoistinganotor 96 are then operated to hoist the Clipper 84 and permit the excavated material to run down the clipper handle and discharge onto the conveyor 16. This position is especially shown by the full lines in Fig. 1. The excavated material will discharge gravitally thru the dipper handle onto the conveyor and will then be carried rearwardly of the machine' and discharged over the end of the conveyor into the waiting mine cars 54. As soon as thedipper has discharged its load of excavated material, the controllers may be so operated `that the crowder motor and the hoisting motor permit the clipper to return toits loweremost position, as shown by the dotted 4lines of l., and again be crowded into the bank of material to be excavated. The process is repeated a number of times until it is again necessary to move the machine forward.

It it desirable in some instances to facilitate the excavating by operation of the propeller motor 18 to rotate the platform at the same timethatthe other motors are working. It is apparent that the various controls may be operated individually or in conjunction in order to secure the desired movement of the dipper and that a great degree of flexibility is obtained by using individual motors. By the operation of the hoisting motor'96, the Crowder motor 77 and the motor 18 to rotate the platform, universal movement ofthe dipper is secured and material may be excavated from any .position `ahead of the machine and to the sides thereof. Since the forward end of the conveyor ismounted substantially over the center of rotation of the rotatable platform, the clipper will discharge into the conveyor no matter thru what angle the rotatable platform is'turned. When suilicient material has been excavated ahead of the machine to warrant movement of the machine farther ahead, the propeller motor 18 may be disengaged from the mechanism which causes it to rotate the rotatable platform 11 and may again be engaged with the propelling gearing 33 by meansof the dog clutches 22 and 31. lf it is notl desired to lay tracks ahead of the machine, the propeller motor may be actuated nevertheless and the machine driven onto the floor of the tunnel. The wide wheels preclude the sinking of the machine into the earth.

It will be appreciated that in our excavator we have provided a machine which can excavate material from a very narrow and low mine and discharge it to the rear without necessitating asemi-circular horizontal movement of the v*clipper from the front of the machine to the rear in order to discharge, yand that our machine for that reason can ibe lused in tunnels oli-comparatively small dimensions.

le claim: 4

1. In an excavator, a mast, a clipper ful'- crumed on said mast, a hoisting cable attached to said dipper and passing `upwardly over a pulley and then downwardly, and a purchase 'arm rotatable about said fulcrufmy with said clipper and adapted tol miga-ge said cable'a's it passes upwardly over said pulley or as it passes downwardly.

excavator, a pair 'of masts,a crowder shaft extending between said masts, a uni'- tary dipper and Clipper handle, longitudinal keyways on said unitary dipper and dip-per hand-le, purchase arms journalled concentric with said Crowder shaft, and keys on said purchase arms forengagement withsaid keywaysln testimony whereof, wehave hereunto set Y 

